E90 320D 2010 Immobiliser or Battery

[Bimmer84]

Folks, I am having starting problems with my 320D E90. The immobiliser doesn't respond to keyfob at all sometimes. The only response I get is an alarm/tone coming from rear wheel arch area. I can manually enter the car however inserting the fob in car doesn't do anything either. It appears that everything is dead which at the time makes me think that its the battery. however half an hour to 4 hours later, car starts with no problem. The battery is original from new and its coming up to 6 years.

This seems to happen on morning after cold nights or rainy days in milder weather. Can someone please tell me where the problem may lie and what would be a good starting point in order to investigate and eventually rectify this issue.

[Bimmer Owners' Club]

 

I would immediately suspect the battery as intermittently failing after being 6 years old and following cold nights but a heavy discharge test would confirm this.

 

[Official NOCO]

Yes this definitely sounds like you need a new battery. Especially with the cold weather issue! 

[Bimmer84]

Thanks guys for the advice. I took to a german car specialist garage to understand the likely problem with it. Upon explaining the failure mode he immediate pointed me to a loose 'Battery to Fusebox connection' which is in the passenger footwell of my BMW. I weren't sure about this so he opened the foot well panel, the red live wire from Battery (in the boot) was connected to the fuse box, he shook the wire with little force and the door open light in the interior started to flicker. Now I am kind of sure that that may have bene the problem but I will have to wait and see whether the said fault reappears. The guy was adamant that it is a common problems that the connection works itself loose.

I will still though start saving up for a new battery. Any idea how much a genuine BMW replacement will set me back?

[Bimmer Owners' Club]

Good diagnosis...the Wiggle Test as it was known as at Ford.

Batteries are quite reasonably priced at Halfords, especially the Premium range (much better quality)

[Rich2]

Just seen this post. I believe that my 320i was subject to a manufacturer recall because of this issue.

[Bimmer Owners' Club]

Seems like it is a common problem which can affect other models also...how it comes loose in the first place is another question

[Bimmer84]

14 hours ago, Rich2 said:

Just seen this post. I believe that my 320i was subject to a manufacturer recall because of this issue.

yes, seems only the petrol version was recalled. Mine is a diesel.

4 minutes ago, Trevor said:

Seems like it is a common problem which can affect other models also...how it comes loose in the first place is another question

he said that rust causes it, but it was enclosed in the passenger footwell so not sure : | but it has not happened since so the loose connection must have been the immediate cause .

[Bimmer Owners' Club]

sounds like a logical cause...being in an enclosed environment as temperature changes I suppose will cause a certain amount of condensation and then leads to corrosion.

[Keith Faulkner]

On ‎17‎/‎06‎/‎2016 at 1:13 PM, Bimmer84 said:

Folks, I am having starting problems with my 320D E90. The immobiliser doesn't respond to keyfob at all sometimes. The only response I get is an alarm/tone coming from rear wheel arch area. I can manually enter the car however inserting the fob in car doesn't do anything either. It appears that everything is dead which at the time makes me think that its the battery. however half an hour to 4 hours later, car starts with no problem. The battery is original from new and its coming up to 6 years.

This seems to happen on morning after cold nights or rainy days in milder weather. Can someone please tell me where the problem may lie and what would be a good starting point in order to investigate and eventually rectify this issue.

Hi, 6 years is a good age for a battery, its bound to be feeling its age. If you have a battery charger, couple it up and see if it shows a high charging rate just after the problem occurs, and this indicates your battery is low or flat. Otherwise have your battery tested by a reliable Garage. I had the same trouble during a very cold spell recently, I charged the battery and have had no trouble since but my battery was on the car when I bought it so I dont know how old it is.